In general, the basic processes for processing color light-sensitive materials are a color developing process and a desilvering process. In the color developing process, the silver halide exposed to light is reduced with a color developing agent to form elemental silver and simultaneously the oxidized color developing agent reacts with a coloring agent (coupler) to form dye images. In the subsequent desilvering process, the elemental silver formed during the color developing process is oxidized by the action of an oxidizing agent (in general, referred to as "bleaching agent") and then is dissolved by the action of a complexing agent for silver ions generally referred to as "fixing agent". Only the dye images remain on the color light-sensitive materials after the desilvering process.
The desilvering process described above generally comprises two processing baths, one of which is a bleaching bath containing a bleaching agent and the other of which is a fixing bath containing a fixing agent; or only one bath simultaneously containing a bleaching agent and a fixing agent.
The practical development processing further comprises, in addition to the foregoing basic processes, a variety of auxiliary processes for the purposes of maintaining photographic and physical properties of images, enhancing storability of images or the like. Examples of such auxiliary processes are a film hardening bath, a stopping bath, an image stabilizing bath and a water washing bath.
The bleaching agents used in the desilvering process are in general red prussiate of potash, bichromates, ferric chloride, ferric complexes of aminopolycarboxylic acids and persulfates.
However, a problem of environmental pollution arises when red prussiate of potash and bichromates are employed and the use thereof requires a specific installation for processing the same. In addition, if the ferric chloride is used, it accompanies the formation of iron hydroxide and the generation of stains during the subsequent water washing process. Thus, it is difficult to practically use such bleaching agents because of various practical obstacles mentioned above. Regarding the persulfates, the bleaching ability thereof is very weak and it takes a long period of time for bleaching. To eliminate this problem, there is proposed a method in which a bleaching accelerator is simultaneously used for enhancing the bleaching ability. However, the persulfates per se is specified as dangerous materials in accordance with the Fire Services Act. The use thereof is restricted, it is needed to take various steps in storing the same and thus practical use thereof is very difficult.
One the other hand, ferric complexes of aminopolycarboxylic acids, in particular ferric complex of ethylenediaminetetraacetic acid and ferric complex of diethylenetriaminepentaacetic acid have widely been used as a bleaching agent since they cause no environmental pollution and no problem of storage as in the case of persulfates. However, the ferric complexes of aminopolycarboxylic acids do not exhibit sufficient bleaching ability. A low sensitive silver halide color light-sensitive material mainly composed of a silver chlorobromide emulsion can be bleached with a solution containing such a ferric complex as a bleaching agent. But, if it is intended to process a highly sensitive color light-sensitive material which is mainly composed of a silver chloroiodobromide or silver iodobromide emultion and which is sensitized with a color sensitizer, in particular a photographic color reversal light-sensitive material and a photographic color negative light-sensitive material in which an emulsion having a high silver content is used, the desilvering is insufficient and it takes a long time for performing bleaching.
For instance, if a photographic color negative light-sensitive material is bleached with a bleaching solution containing a ferric complex of aminopolycarboxylic acid, the required bleaching time is at least 4 minutes and complicated operations such as the control of the pH value of the bleaching solution and aeration process are necessary to hold the bleaching ability thereof. Even when such complicated operations are practically performed, insufficient bleaching is often observed.
Moreover, the bleaching process must be followed by processing with a fixing solution for at least 3 minutes, which leads to further elongation of the desilvering process. Therefore, there is a demand for reducing the processing time.
Particularly, minilab processing has recently spread and, therefore, reduction of processing time is quite important to improve the efficiency of the minilab and to provide users with quick services. However, it is found that the reduction of time required for a desilvering step causes difficulties on improvement of the desilvering speed and raises stain (Dmin) of processed light-sensitive materials. Among them, increase in the magenta stain is remarkable.
It is also required to reduce the amount of waste liquor derived from photographic processing from the viewpoint of preventing environmental pollution and, in the desilvering process, it becomes an important subject to reduce the amount of waste liquor or to reduce the amount of a bleach-fixing solution to be replenished.
German Patent No. 866,605 discloses a bleach-fixing solution containing a ferric complex of aminopolycarboxylic acid and a thiosulfate in one solution to make the disilvering process more rapid. However, if a ferric aminopolycarboxylate which inherently exhibits low oxidation ability (bleaching ability) coexists with a thiosulfate having reducing ability, the bleaching ability thereof is extremely lowered and thus it cannot practically be used as a bleach-fixing solution for sufficiently desilvering highly sensitive photographic color light-sensitive materials having a high silver content. There has been proposed various methods for eliminating such drawbacks of the bleach-fixing solution, for instance, a method in which an iodide or bromide is added thereto as disclosed in U.K. Patent No. 926,569 and Japanese Patent Publication for Opposition Purpose (hereunder referred to as "J.P. KOKOKU") No. 53-11854; a method in which a ferric aminopolycarboxylate is contained in a high content using a triethanolamine as disclosed in Japanese Patent Unexamined Publication (hereunder referred to as "J.P. KOKAI") No. 48-95834. However, these methods do not provide sufficient effects and, therefore, they cannot practically be employed.
In addition to the insufficient desilvering, the bleach-fixing solution has a further severe problem that cyan dyes formed during color development are reduced by the solution to form leuco dyes and to thus impair color reproduction of the light-sensitive material. As discussed in the specification of U.S. Pat. No. 3,773,510, it is known that this problem can be solved by increasing the pH value of the bleach-fixing solution. However, as pH increases, the bleaching ability on the contrary is extremely lowered and thus the increase in the pH value cannot practically be adopted. U.S. Pat. No. 3,189,452 discloses a method for oxidizing the leuco dyes with a bleaching solution containing red prussiate of potash to convert them into cyan dyes, after the bleach-fixing process. However, the use of red prussiate of potash causes the environmental pollution and even if the light-sensitive materials are additionally bleached after the bleach-fixing process, it is almost impossible to reduce the amount of silver.
By the way, there have been conducted various studies to develop a means for recovering silver as a valuable noble metal from bleach-fixing and/or fixing solutions, for instance, a method for recovering silver by introducing a bleach-fixing solution in an electrolytic cell and then electrolyzing it; a method for recovering silver by diluting the bleach-fixing solution to lower the solubility of a silver salt to precipitate the same; a method for recovering silver by adding sodium sulfide to those solutions in order to form silver sulfide; or a method for recovering silver, in the form of ions, by passing the bleach-fixing solution through a column packed with a large amount of an ion-exchange resin. Such means for recovering silver are detailed in, for instance, Kodak Publication, J-10 (Recovering Silver From Photographic Materials), issued by Kodak Industrial Division; J.P. KOKOKU No. 58-22528; J.P. KOKAI No. 54-19496; Belgian Patent No. 869,087; and DEOS No. 2,630,661.
However, these methods are developed to recover silver from bleach-fixing solutions, but not to reuse the solutions obtained after the recovery of silver. Therefore, there are various obstacles to reuse such bleach-fixing solutions after desilvering. For instance, the bleach-fixing solutions obtained after desilvering cannot be reused or it is necessary to add components which are lost during the recovery of silver to reuse the same (addition of a regenerant). As described above, it has not yet been realized to simultaneously reduce the amount of waste liquor and rapidly carry out the desilvering process while recovering silver.
Accordingly, an object of the present invention is to provide a method for processing silver halide color photographic light-sensitive materials, which comprises a rapid bleaching process capable of reducing the amount of waste bleaching solution.
Further, an object of the present invention is to provide a method for processing silver halide color photographic light-sensitive materials, which comprises a rapid bleaching process capable of reducing the stain.
The aforementioned objects of the present invention can effectively be achieved by providing a method which comprises the steps of color developing a silver halide color photographic light-sensitive material having at least one silver halide emulsion layer containing silver bromoiodide on a substrate and then desilvering the same. The method is characterized in that the bleaching process is carried out in the presence of a bleaching accelerator and that the bleaching process is carried out while a part or whole of a bleaching solution is brought into contact with a strong basic anion-exchange resin.
The inventors of this invention have conducted various studies and have found that a bleaching solution deteriorated due to processing of photographic light-sensitive materials containing silver iodide comprises a large amount of silver ions and a small amount of iodide ions and that the bleaching ability thereof is extremely lowered due to the presence of both these ions. However, if silver ions present in the deteriorated bleaching solution are recovered by any means for recovering silver as described above, the thiosulfate serving as a fixing agent or sulfite ions serving as a preservative thereof are decomposed or removed during the recovery of silver.
Contrary to this, the inventors of this invention have found that the bleaching ability of the solution can be recovered by removing iodide ions present in a small amount, although silver ions are still present therein and that the iodide ions can selectively be removed from the deteriorated bleaching solution by bringing it into contact with an anion-exchange resin.
It has been un-expected that the bleach-accelerating action is extremely improved by using a bleaching accelerator, particularly an organic bleaching accelerator when iodide ions in the bleaching solution are reduced by the method of the present invention. This effect is remarkable when the amount of iodide ions is 0.5 g/l or less, particularly 0.3 g/l or less, expressed in the amount of KI.
As mentioned above, the amount of iodide ions can be reduced and as a result, the replenishing amount of the bleaching solution can be reduced and, at the same time, the amount of the waste solution can be reduced. Whereby it becomes possible to provide a rapid bleaching processing with low-cost and low probability of environmental pollution.
The light-sensitive materials which are processed by the method of the present invention comprises at least one silver halide emulsion layer containing at least one mole % of silver iodide, preferably 5 to 25 mole % and more preferably 7 to 20 mole %.
Therefore, in the method of this invention, there may be processed a color light-sensitive material comprising a substrate provided thereon with at least one layer of silver halide emulsion which contains at least one silver iodide selected from the group consisting of silver iodide, silver iodobromide, silver chloroiodobromide and silver chloroiodide. In this respect, silver chloride and silver bromide may optionally be used in addition to the foregoing silver iodide.
The silver halide grains used in the color photographic light-sensitive materials processed by the method of the invention may be in any crystalline forms such a regular crystalline form as a cubic, octahedral, rhombododecahedral or tetradecahedral form; such an irregular form as a spheric or tabular form; or a composite form thereof. In addition, they may be tabular grains having an aspect ratio of not less that 5 as disclosed in Research Disclosure, Vol. 225, pp. 20-58 (January, 1983).
The silver halide grains may be those having epitaxial structure or those having a multilayered structure whose internal composition (such as halogen composition) differs from that of the surface region.
The average grain size of silver halide is preferably not less than 0.5.mu., more preferably in the range of 0.7 to 5.0.mu..
The grain size distribution thereof may be either wide or narrow. The emultions comprising a silver halide having a narrow grain size distribution is known as so-called monodisperse emulsions whose dispersion coefficient is preferably not more than 20% and more preferably not more than 15%. The "dispersion coefficient" herein means the standard deviation divided by the average grain size.
The photographic emulsions may comprise any combination of silver chloride, silver bromide, silver iodide, silver iodobromide, silver chloroiodobromide and silver chloroiodide.
The coated amount of silver in the light-sensitive materials processed by the invention is generally 1 to 20 g/m.sup.2, preferably 2 to 10 g/m.sup.2, provided that the total amount of iodine (AgI) present in the silver halide light-sensitive materials is preferably not less than 4.times.10.sup.-3 mole/m.sup.2 and more preferably 6.times.10.sup.-3 to 4.times.10.sup.-2 mole/m.sup.2.
The effect of the invention is insufficient when the amount of silver coated on a light-sensitive material is less than 2 g/m.sup.2. The use of more than 10 g/m.sup.2 of silver makes the bleaching power (desilvering) insufficient and may give an unsatisfactory result.
The silver halide emulsions may contain other salts or complexes such as cadmium salts, zinc salts, lead salts, thallium salts, iridium salts or complex salts thereof, rhodium salts or complex salts thereof and iron salts or complex salts thereof, which are added thereto during the formation of silver halide grains or a physical ripening process.
The bleaching accelerators, preferably organic bleaching accelerators, which are added to a bleaching bath, the bath preceeding it or the light-sensitive layer may be selected from compounds having mercapto groups or disulfide bonds; thiazolidine derivatives, thiourea derivatives and isothiourea derivatives, so far as they show a bleaching acceleration effect and preferred examples thereof are those represented by the following general formula (IA) to (VIA): EQU R.sup.1A --S--M.sup.1A (IA)
In the general formula, M.sup.1A represents a hydrogen atom, an alkali metal atom or an ammonium residue; and R.sup.1A represents an alkyl, alkylene, aryl or heterocyclic group. Preferably the alkyl group has 1 to 5, more preferably 1 to 3 carbon atoms. The alkylene group preferably has 2 to 5 carbon atoms. Examples of the aryl group include phenyl and naphthyl groups, preferably phenyl group. Preferred examples of the heterocyclic groups include nitrogen atom-containing 6-membered rings such as pyridine and triazine; and nitrogen atom-containing 5-membered rings such as azole, pyrazole, triazole and thiazole. Particularly groups containing at least two nitrogen atoms as ring-forming atoms are more preferred. R.sup.1A may be substituted with substituents. Examples of such substituents are alkyl, alkylene, alkoxy, aryl, carboxyl, sulfo, amino, alkylamino, dialkylamino, hydroxyl, carbamoyl, sulfamoyl and sulfonamido groups.
Preferred compounds represented by the general formula (IA) are those represented by the following general formulas (IA-1) to (IA-4): ##STR1##
In the formula, R.sup.2A, R.sup.3A and R.sup.4A may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted lower alkyl group (preferably those having 1 to 5 carbon atoms, in particular a methyl, ethyl or propyl group) or an acyl group (preferably those having 1 to 3 carbon atoms, such as an acetyl or propionyl group) and kA is an integer of 1 is 3. Z.sup.1A represents an anion such as chloride ion, bromide ion, nitrate ion, sulfate ion, p-toluenesulfonate ion or oxalate ion. hA is 0 or 1 and iA is 0 or 1.
R.sup.2A and R.sup.3A may be bonded together to form a ring. Particularly preferred group R.sup.2A, R.sup.3A or R.sup.4A is a substituted or unsubstituted lower alkyl group.
Examples of substituents of R.sup.2A, R.sup.3A and R.sup.4A are hydroxyl, carboxyl, sulfo and/or amino groups. ##STR2##
In the general formulas, R.sup.5A represents an hydrogen atom, a halogen atom such as a chlorine or bromine atom, an amino group, a substituted or unsubstituted lower alkyl group preferably having 1 to 5 carbon atoms (particularly, a methyl, ethyl or propyl group), an amino group having alkyl group(s) such as a methylamino, ethylamino, dimethylamino or diethylamino group, or a substituted or unsubstituted alkylthio group.
Examples of substituents of R.sup.5A are a hydroxyl group, a carboxyl group, a sulfo group, an amino group, or an amino group having an alkyl group. EQU R.sup.1A --S--S--R.sup.6A (IIA)
In the formula, R.sup.1A is the same as that in the general formula (IA) and R.sup.6A has the same meaning as that of R.sup.1A. R.sup.1A and R.sup.6A may be the same or different.
Preferred compounds represented by formula (IIA) are those represented by the following general formula (IIA-1): ##STR3##
In the formula, R.sup.7A, R.sup.8A and R.sup.9A have the same meanings as R.sup.2A, R.sup.3A and R.sup.4A defined above. hA, kA and Z.sup.1A are the same as those in formula (IA-1). iB is 0, 1 or 2. ##STR4##
In formula (III), R.sup.10A and R.sup.11A may be the same or different and each represents a hydrogen atom, an alkyl group optionally having substituents, preferably a lower alkyl group such as a methyl, ethyl or propyl group, a phenyl group optionally having substituents, a heterocyclic group optionally having substituents, more specifically a heterocyclic group including at least one hetero atom selected from the group consisting of nitrogen, oxygen, sulfur atoms or the like, such as a pyridine ring, a thiophene ring, a thiazolidine ring, a benzoxazole ring, a benzotriazole ring, a thiazole ring and an imidazole ring; R.sup.12A represents a hydrogen atom or a lower alkyl group optionally having substituents such as a methyl or ethyl group, preferably those having 1 to 3 carbon atoms. Examples of substituents of R.sup.10A to R.sup.12A are a hydroxyl group, a carboxyl group, a sulfo group, an amino group and a lower alkyl group. R.sup.13A represents a hydrogen atom, an alkyl group or a carboxyl group. ##STR5##
In formula (IVA), R.sup.14A, R.sup.15A and R.sup.16A may be the same or different and each represents a hydrogen atom or a lower alkyl group such as a methyl or ethyl group, preferably those having 1 to 3 carbon atoms. kB is an integer of 1 to 5.
X.sup.1A represents an amino group optionally having substituents, a sulfo group, a hydroxyl group, a carboxyl group or a hydrogen atom. Examples of the substituents include substituted or unsubstituted alkyl groups (e.g., methyl, ethyl, hydroxyalkyl, alkoxyalkyl and carboxyalkyl groups) and two alkyl groups may be bonded together to form a ring. R.sup.14A, R.sup.15A and R.sup.16A may be bonded together to form a ring. Preferred examples of R.sup.14A to R.sup.16A are a hydrogen atom, a methyl group or an ethyl group; those of X.sub.1A include an amino group or a dialkylamino group. ##STR6##
In formula (VA), A.sup.1A is an aliphatic linking group, an aromatic linking group or a heterocyclic linking group with a valency of n, wherein A.sup.1A is simply an aliphatic, aromatic or heterocyclic group when n is 1.
Alkylene groups having 3 to 12 carbon atoms such as trimethylene, hexamethylene, cyclohexylene are exemplified as the aliphatic linking group represented by A.sup.1A.
Examples of the aromatic linking groups include arylene groups having 6 to 18 carbon atoms such as phenylene and naphthylene groups.
Examples of the heterocyclic linking groups include heterocyclic groups comprising at least one hetero atom such as oxygen, sulfur and nitrogen atom (e.g., thiophene, furantriazine, pyridine and piperidine).
Generally, the aliphatic, aromatic or heterocyclic linking group comprises a single group, but they may be those comprising two or more of these bonded together directly or through a bivalent linking group (e.g., --O--, --S--, R.sup.20A N&lt;, --SO.sub.2 --, --CO-- or those formed by combining these groups; R.sup.20A represents a lower alkyl group).
These aliphatic, aromatic and heterocyclic linking groups may have substituents.
Examples of such substituents are alkoxy groups, halogen atoms, alkyl groups, hydroxyl group, carboxyl group, sulfo group, sulfonamido group and sulfamoyl group.
X.sup.2A represents --O--, --S--, R.sup.21A --N&lt; (wherein R.sup.21A is a lower alkyl group such as a methyl or ethyl group); R.sup.17A and R.sup.18A each represents a substituted or unsubstituted lower alkyl group (e.g., methyl, ethyl, propyl, isopropyl or pentyl group) and preferred examples of the substituents are hydroxyl, lower alkoxy groups such as methoxy, methoxyethoxy and hydroxyethoxy groups, amino groups such as unsubstituted amino, dimethylamino and N-hydroxyethyl-N-methylamino groups. If there are two or more substituents, they may be the same or different.
R.sup.19A represents a lower alkylene group having 1 to 5 carbon atoms such as methylene, ethylene, trimethylene and methylmethylene; Z.sup.2A represents an anion such as a halide ion (e.g., a bromide or chloride ion), a nitrate ion, a sulfate ion, p-toluenesulfonate ion or an oxalate ion.
R.sup.17A and R.sup.18A may be linked through a carbon or hetero atom (such as oxygen, nitrogen or sulfur atom) to form a 5- or 6-membered heterocyclic ring such as a pyrrolidine, piperidine, morpholine, triazine or imidazolidine ring.
R.sup.17A (or R.sup.18A) and A may be linked through a carbon or hetero atom (such as an oxygen, nitrogen or sulfur atom) to form a 5- or 6-membered heterocyclic ring such as a hydroxyquinoline, hydroxyindole or isoindoline ring.
Moreover, R.sup.17A (or R.sup.18A) and R.sup.19A may be linked through a carbon or hetero atom (such as oxygen, nitrogen or sulfur arom) to form a 5- or 6-membered heterocyclic ring such as a piperidine, pyrrolidine or morpholine ring.
lA is 0 or 1; mA is 0 or 1; nA is 1, 2 or 3; pA is 0 or 1; and qA is 0, 1, 2 or 3. ##STR7##
In the formula, X.sup.1A and kB are the same as those in the general formula (IVA).
M.sup.2A represents a hydrogen atom, an alkali metal atom, an ammonium or --S--CS--NR.sup.22A --(CH.sub.2)kB--X.sup.1A wherein R.sup.22A represents a hydrogen atom or a lower alkyl group which has 1 to 5 carbon atoms and may be substituted.
Specific examples of the compounds represented by formulas (IA) to (VIA) are as follows: ##STR8##
Biscations and bisamines as disclosed in J.P.A. (Japanese Patent Application Serial) Nos. 62-143467, 62-185030, 62-185031, 62-274094, 62-274095 and 62-277580 can be used as bleaching accelerators in addition to the foregoing compounds.
The above listed compounds may be prepared according to any known methods. More specifically, compounds (I) may be prepared by the method disclosed in U.S. Pat. No. 4,285,984; G. Schwarzenbach et al., Helv. Chim. Acta, 1955, Vol. 38, p. 1147; and R. O. Clinton et al., J. Am. Chem. Soc., 1948, Vol. 70, p. 950; compounds (II) by the method disclosed in J.P. KOKAI No. 53-95630; compounds (III) and (IV) by the method disclosed in J.P. KOKAI No. 54-52534; compounds (V) by the method disclosed in J.P. KOKAI Nos. 51-68568, 51-70763 and 53-50169; compounds (VI) by the method disclosed in J.P. KOKOKU No. 53-9854 and J.P. KOKAI No. 59-214855; and compounds (VII) by the method disclosed in J.P. KOKAI No. 53-94927.
The amount of the bleaching accelerators to be added to the bleaching solution used in the invention may vary depending on the kinds of the photographic light-sensitive materials to be processed, processing temperature, processing time of the intended process and the like, but it is desirably in the range of 1.times.10.sup.-5 to 1.times.10.sup.-1 mole, preferably 1.times.10.sup.-4 to 5.times.10.sup.-2 mole per liter of the bleaching solution.
These compounds may in general be added to the bleaching solution in the form of a solution in water, an alkaline solution, an organic acid or an organic solvent. Alternatively, it is also possible to directly add powder to the bleaching solution without impairing their effect of accelerating bleaching process.
In the present invention, any commercially available resins may be used as the anion-exchange resins. Particularly, a basic anion-exchange resin is preferably used as the anion-exchange resins of the present invention.
Preferred basic anion-exchange resins used in the invention are represented by the formula (VIII): ##STR9##
In the formula, A represents a monomer unit obtained by copolymerizing copolymerizable monomers having at least two ethylenically unsaturated copolymerizable groups and at least one of these groups is present in a side chain. B represents a monomer unit obtained by copolymerizing ethylenically unsaturated copolymerizable monomers. R.sup.13 represents a hydrogen atom, a lower alkyl group or an aralkyl group.
Q represents a single bond, or an alkylene group, a phenylene group, an aralkylene group ##STR10## Wherein L represents an alkylene, arylene or aralkylene group and R is an alkyl group.
G represents ##STR11## and R.sub.14, R.sub.15, R.sub.16, R.sub.17, R.sub.18, R.sub.19, R.sub.20 and R.sub.21 may be the same or different and may be substituted and each represents a hydrogen atom, an alkyl, anyl or aralkyl group. X.sup.- represents an anion. Two or more groups selected from Q, R.sub.14, R.sub.15 and R.sub.16 or Q, R.sub.17, R.sub.18, R.sub.19, R.sub.20 and R.sub.21 may be bonded to form a ring structure together with the nitrogen atom.
x, y and z each represents molar percentage, x ranges from 0 to 60, y from 0 to 60 and z from 30 to 100.
The foregoing general formula (VIII) will hereunder be explained in more detail. Examples of monomers from which A is derived are divinylbenzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl grlycol dimethacrylate and tetramethylene glycol dimethacrylate and particularly divinylbenzene and ethylene glycol dimethacrylate are preferred.
A may comprise at least two of the foregoing monomer units.
Examples of ethylenically unsaturated monomer from which B is derived include ethylene, propylene, 1-butene, isobutene, styrene, .alpha.-methylstyrene, vinyltoluene, monoethylenically unsaturated esters of aliphatic acids (e.g., vinyl acetate and allyl acetate), esters of ethylenically unsaturated monocarboxylic acids or dicarboxylic acids (e.g., methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, bonzyl methacrylate, n-butyl acrylate, n-hexyl acrylate and 2-ethylhexyl acrylate), monoethylenically unsaturated compounds (e.g., acrylonitrile), or dienes (e.g., butadiene and isoprene). Particularly preferred are styrene, n-butyl methacrylate and cyclohexyl methacrylate. B may comprise two or more of the foregoing monomer units.
R.sub.13 preferably represents a hydrogen atom, a lower alkyl group having 1 to 6 carbon atoms such as a methyl, ethyl, n-propyl, n-butyl, n-amyl or n-hexyl group or an aralkyl group such as a benzyl group and particularly preferred are a hydrogen atom and a methyl group.
Q preferably represents a divalent optionally substituted alkylene group having 1 to 12 carbon atoms such as a methylene, ethylene or hexamethylene group, an optionally substituted arylene group such as a phenylene group, or an optionally substituted aralkylene group having 7 to 12 carbon atoms such as ##STR12## and groups represented by the following ##STR13##
Wherein L preferably represents an optionally substituted alkylene group having 1 to 6 carbon atoms, or an optionally substituted arylene group or an optionally substituted aralkylene group having 7 to 12 carbon atoms, more preferably an optionally substituted alkylene group having 1 to 6 carbon atoms. R is preferably an alkyl group having 1 to 6 carbon atoms.
G represents ##STR14## and R.sub.14, R.sub.15, R.sub.16, R.sub.17, R.sub.18, R.sub.19, R.sub.20 and R.sub.21 may be the same or different and each represents a hydrogen atom, an alkyl having 1 to 20 carbon atoms, an aryl having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms. These alkyl, aryl and aralkyl groups include substituted alkyl, aryl and aralkyl groups.
Examples of alkyl groups include such unsubstituted alkyl groups as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, t-butyl, n-amyl, iso-amyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl and n-dodecyl groups. The number of carbon atoms of the alkyl group preferably ranges from 1 to 16 and more preferably 4 to 10.
Examples of substituted alkyl groups are alkoxyalkyl groups such as methoxymethyl, methoxyethyl, methoxybutyl, ethoxyethyl, ethoxypropyl, ethoxybutyl, butoxyethyl, butoxypropyl, butoxybutyl and vinyloxyethyl; cyanoalkyl groups such as 2-cyanoethyl, 3-cyanopropyl and 4-cyanobutyl; halogenated alkyl groups such as 2-fluoroethyl, 2-chloroethyl and 3-fluoropropyl; alkoxycarbonylalkyl groups such as ethyoxycarbonylmethyl; allyl group, 2-butenyl group and propargyl.
Examples of aryl groups include such unsubstituted aryl groups as phenyl and naphthyl groups; such substituted aryl groups as alkylaryl groups (e.g., 2-methylphenyl, 3-methylphenyl, 4-mehylphenyl, 4-ethylphenyl, 4-isopropylphenyl and 4-t-butylphenyl); alkoxyaryl groups (e.g., 4-methoxyphenyl, 3-methoxyphenyl and 4-ethoxyphenyl); and aryloxyaryl groups (e.g., 4-phenoxyphenyl). The number of carbon atoms of the aryl group preferably ranges from 6 to 14, more preferably 6 to 10. Particularly preferred is a phenyl group.
Examples of aralkyl groups include unsubstituted aralkyl groups such as benzyl, phenethyl, diphenylmethyl and naphthylmethyl; substituted aralkyl groups such as alkylaralkyl groups (e.g., 4-methylbenzyl, 2,5-dimethylbenzyl and 4-isopropylbenzyl), alkoxyaralkyl groups (e.g., 4-methoxybenzyl and 4-ethoxybenzyl), cyanoaralkyl groups (e.g., 4-cyanobenzyl), perfluoroalkoxyaralkyl groups (e.g., 4-pentafluoropropoxybenzyl and 4-undecafluorohexyloxybenzyl) and halogenoaralkyl groups (e.g., 4-chlorobenzyl, 4-bromobenzyl and 3-chlorobenzyl). The number of carbon atoms of the aralkyl group preferably ranges from 7 to 15 and more preferably 7 to 11. Among these, benzyl and phenethyl groups are particularly preferred.
R.sub.14, R.sub.15 and R.sub.16 each preferably represents an alkyl or aralkyl group, in particular they represent alkyl groups whose total number of carbon atoms ranges from 12 to 30.
R.sub.17 to R.sub.21 each preferably represents a hydrogen atom or an alkyl group.
X.sup..crclbar. represents an anion such as a hydroxide ion, a halogen ion (e.g., chloride or bromide ion), an alkyl- or arylsulfonate ion (e.g., a methanesulfonate, ethanesulfonate, benzenesulfonate or p-toluenesulfonate ion), an acetate ion, a sulfate ion and a nitrate ion. Particularly preferred are chloride, acetate and sulfate ions.
At least two groups selected from Q and R.sub.14 to R.sub.16 may be preferably be bonded to form a ring structure together with the nitrogen atom. Examples of such rings preferably include pyrrolidine, piperidine, morpholine, pyridine, imidazole and quinuclidine rings. Particularly preferred are pyrrolidine, morpholine, piperidine, imidazole and pyridine rings.
At least two groups selected from Q and R.sub.17 to R.sub.21 may be bonded to form a ring structure together with the nitrogen atom. Particularly preferred are 5- or 6-membered ring structures.
The basic anion-exchange resins of the invention may comprise two or more of the foregoing monomer units: ##STR15##
x ranges from 0 to 60 mole %, preferably 0 to 40 mole %, and more preferably 0 to 30 mole %. y ranges from 0 to 60 mole %, preferably 0 to 40 mole % and more preferably 0 to 30 mole %. z ranges from 30 to 100 mole %, preferably 40 to 95 mole % and more preferably 50 to 85 mole %.
Among the compounds represented by formula (VIV), particularly preferred are those represented by the following general formula (IX): ##STR16##
In the formula, A, B, x, y, z, R.sub.13 to R.sub.16, and X.sup.- are the same as those in the general formula (VIII).
More preferred are those represented by formula (IX) in which all of the groups R.sub.2 to R.sub.4 are alkyl groups whose total number of carbon atoms ranges from 12 to 30.
Specific examples of the basic anion-exchange resins of the present invention represented by the general formula (VIII) will be listed below, but the compounds of this invention are not restricted to these specific examples. ##STR17##
In the present invention, any commercially available resins may be used as the strong basic anion-exchange resins. Specific examples thereof include Amberlite IRA-410, IRA-411, IRA-910, IRA-400, IRA-401, IRA-402, IRA-430, IRA-458, IRA-900, IRA-904 and IRA-938 (all these being available from Rohm & Haas Co., Ltd.); DIAION SA 10A, SA 12A, SA 20A, SA 21, PA 306, PA 316,
318, PA 406, PA 412 and PA 418 (all these being available from MITSUBISHI CHEMICAL INDUSTRIES LTD.) and EPOLUS K-70 (available from MIYOSHI FAT & OIL CO., LTD.).
Moreover, they may be synthesized in accordance with the following Preparation Examples.